High-Low Hitch Extension and Dual Hitch Receiver
Installation Instructions and User's Guide
for the ROADMASTER 048 and 070 series of high-low hitch extensions and the 077 series of dual hitch receivers
All specifications are subject to change without notice.
854326-02 01-11
ROADMASTER, Inc.
6110 NE 127th Ave.
Vancouver, WA 98682
NOTE: the 048 and 070 series high-low hitch receiver extensions can be rotated up or down, for high- or low-ground
clearance.
The 077-2 Dual Hitch Receiver will adjust the towing
system down two inches; the 077-4 Dual Hitch Receiver will
adjust the towing system down two inches or four inches,
depending on which way it is rotated.
Installation instructions
1. Slide the end of the extension into the motorhome hitch
receiver, align the holes and secure the extension to the
receiver with a hitch pin and clip (not included).
800-669-9690
Fax: 360-735-9300
www.roadmasterinc.com
Towing and tongue weight capacities
The maximum towing capacity and tongue weight
of 048 and 070 series high-low hitch extensions and
the 077 dual hitch receivers are as follows:
Maximum
towing
capacity
Maximum
tongue
weight
048 series ................ 10,000 pounds ....... 400 pounds
(part numbers 048-2, 048-4, 048-6, 048-8, 048-10)
070 series .................. 6,000 pounds ....... 100 pounds
(part numbers 072, 070, 076)
077 series ................ 10,000 pounds ....... 400 pounds
(part numbers 077-2 and 077-4, patent number 5,884,930)
Use hitch pins with 5/8" diameters only. Hitch pins
with smaller diameters will break during towing, which
may cause the extension, and the towed vehicle with
it, to separate from the motorhome.
Failure to follow these instructions may cause property damage, personal injury or even death.
2. Next, insert the tow bar stinger or ball hitch mount into
the other end of the extension
As before, secure the stinger or ball hitch mount to the
extension with a hitch pin and clip.
NOTE: to prevent theft or accidental release, ROADMASTER recommends substituting a receiver hitch lock (part
number 315) for at least one of the hitch pins and clips.
Do not use more than one hitch receiver exten-
IMPORTANT NOTICE!
Safety definitions
These instructions contain information that is very
important to know and understand. This information
is provided for safety and to prevent equipment problems. To help recognize this information, observe the
following symbols:
WARNING indicates a potentially hazardous
situation which, if not avoided, could result in
property damage, serious personal injury or even
death.
NOTE
Refers to important information and is placed in
italic type. It is recommended that you take special
notice of these items.
“Maximum towing capacity” is the maximum allowable weight of the fully loaded vehicle, including its
contents.
“Maximum tongue weight” is the maximum allowable vertical load applied to the extension (including the
weight of any accessory attached to the extension).
Do not exceed the maximum towing capacity or
the maximum tongue weight, or the hitch receiver
extension will fail, which may cause the towed
vehicle to separate from the motorhome.
Property damage, personal injury or even death
can result.
sion at any given time, for any towing application.
The extensions are not designed to be linked to
gether. Multiple extensions will buckle or separate
when towing, causing the towing system to fail.
Significant property damage, personal injury or even
death can result if multiple extensions are used.
Safety cables (or chains) must be used to bypass
the extension and connect the towing vehicle to the
towed vehicle frame to frame. This is required by law
in many states.
Additionally, if the extension is being added to a
tow system with safety cables already in place, be
certain that the safety cables are not too short.
Hitch extensions will extend the distance the safety
cables must now reach. If the safety cables are too
short, severe non-warranty damage will occur to the
safety cables, tow bar or other components of the
towing system.
Damage to the motorhome, and damage to or
continued on next page
continued from preceding page
loss of the towed vehicle, may also occur.
After attaching the hitch receiver extension make
certain there is enough slack in the safety cables at
the motorhome to allow for sharp turns — position the
towed vehicle at a 45 degree angle to the motorhome.
Then measure along the outside contour of the tow
bar from the safety cable connection point at the hitch
receiver to the safety cable connection point at the
towed vehicle.
If the safety cables are shorter than this distance,
you must either: 1) add safety cable extensions (12inch extensions, part number 910648-12, are available
from ROADMASTER); or 2) purchase longer safety
cables.
Do not drill a second hole in the shank of the
hitch receiver, tow bar or hitch receiver extension.
Drilling a second hole will weaken the steel. The
shank may break during towing, which will cause
the towed vehicle to separate. Refer to Figure 1.
If the pre-drilled holes do not align to the hole
in the hitch receiver or the extension: 1) purchase
a hitch accessory of the appropriate length; or 2)
call ROADMASTER technical support.
Failure to follow these instructions may cause
property damage, personal injury or even death.
Failure to follow these instructions may cause
property damage, personal injury or even death.
Do not use the hitch receiver extension if it drags
going over dips, railroad tracks or other uneven road
surfaces. The steel will be severely weakened by the
force of the impact, which will cause the shank (Figure
1) to break.
Inspect the bottom of the extension after the initial
use, and after each trip thereafter, to make certain that
it has not come into contact with the road.
Failure to follow these instructions may cause property damage, personal injury or even death.
Figure 1
Stay within the ‘Safe Zone!’
The primary purpose of a hitch receiver extension of
this type is to bring the tow bar to level — into the ‘Safe
Zone.’ Car-mounted tow bars must be approximately
level; motorhome-mounted tow bars cannot be more
than three inches above level or three inches below
level.
Towing with a tow bar which is not within this range
puts undue strain on the entire towing system. For that
reason, do not tow if the tow bar is not within the Safe
Zone.
To determine if the tow bar is within the Safe Zone
— first, connect the motorhome and vehicle on level
ground. Next, measure the distance from the center
of the motorhome hitch receiver down to the ground.
Then measure the distance from the center of one of
the base pins (Figure 2) on one of the tow bar arms
(Figure 2) down to the ground.
Compare these two measurements. For car-mounted
tow bars, they must be approximately equal; for motorhome-mounted tow bars, they cannot be more than
three inches apart if the base pin is above or below
the motorhome hitch receiver, as shown in Figure 2.
Towing with a tow bar which is not within the Safe
Zone will void the ROADMASTER warranty.
Towing a vehicle with a tow bar that is not within
the Safe Zone will result in significant wear and tear
on the tow bar and brackets, significant wear and
tear on the vehicle’s suspension and frame, and
the eventual failure of the towing system. Property
damage, personal injury or even death can result.
Figure 2